Hand-held vacuum cleaner



Feb. 21, 1961 P. T. HAHN HAND-HELD VACUUM CLEANER 3 Sheets-Sheet 1 Filed NOV. 21 1955 Piu/ 7." 15351222 Feb. 21, 1961 P. T. HAHN HAND-HELD VACUUM CLEANER 3 Sheets-Sheet 2 Filed NOV- 21 1955 3% 1 cm! .7." Hahn fl Feb. 21, 1961 P. T. HAHN HAND-HELD VACUUM CLEANER 3 Sheets-Sheet 3 Filed NOV. 21 1955 3% Pin] 1 A i/m J C United States Patent ffice 2,972,160 Patented Feb. 21, 1961 HAND-HELD VACUUM CLEANER Paul T. Hahn, Milwaukee, Wis., assignor to John Oster Manufacturing Company, Milwaukee, Win, a corporation of Wisconsin Filed Nov. 21, 1955, Ser. No. 547,970

3 Claims. (Cl. 15-344) This invention relates to vacuum cleaners and refers more particularly to small portable hand-held electric vacuum cleaners.

Although the vacuum cleaner of this invention has general utility, it is especially adapted for use by barbers to remove hair clippings from the head, neck and clothing of their customers. Accordingly, it is an object of this invention to provide a vacuum cleaner of this type which although powerful enough to remove small loose hair even from fabric to which it clings tenaciously, nevertheless is small and light enough to be conveniently held in one hand.

Toward the achievement of this general objective, it is another object of the present invention to provide a vacuum cleaner of the type described wherein the suction fan is of the centrifugal type and is mounted in the rear end portion of an elongated hollow housing which not only encloses the fan motor and carries the suction nozzle at its front end but also provides the handle for the appliance, the rear portion of the housing in which the fan is located having air discharge ports in radial alignment with the fan.

This arrangement has three very significant advantages:

First, it permits an efiicient straight through flow of air from the suctionnozzle at the front end of the housing longitudinally through the housing and across the motor to cool it, with a minimum of back pressure since the radially outward discharge of the air directly from the centrifugal'fan involves but a single change in the direction of the air flow;

Second, it assures a well balanced structure and permits the body portion of the housing which serves as a handle, to be smaller in cross section than the diameter of the fan so that the attainment of a comfortable handle is not at the expense of fan capacity, and

Third, it permits the handle forming body portion of the housing to have a generally triangular cross sectional shape which is least fatiguing to hold in the hand and which though large enough to encompass the outline of the motor and also provide a relatively large air passage longitudinally across the motor, nevertheless lies wholly within the boundary of the larger rear portion of the housing in which the fan is located.

Still another object of this invention is to provide a novel manner of mounting the fan and its drive motor in the housing whereby the simple expedient of assembling the body and rear end portions of the housing secures the motor and fan in place in a way which clamps out vibration and electrically insulates the motor from the housing.

A further object of this invention is to provide a guard to protect the operator from touching live parts of the motor while changing the filter, and to use this guard to secure the motor-fan assembly in a predetermined positon of rotation in the housing.

With the above and other objects in view which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

The accompanying drawings illustrate one complete example of the physical embodiment of the invention constructed according to the best mode so far devised for the practical application of the principles thereof, and in which:

Figure 1 is a perspective view of the vacuum cleaner of this invention illustrating the manner in which it is held during use;

Figure 2 is a longitudinal sectional view through the cleaner;

Figure 3 is an exploded perspective view of the rear end portion of the cleaner with parts broken away and in section, illustrating particularly the manner in which the motor and suction fan are mounted;

Figure 4 is a cross sectional view through Figure 2 on the plane of the line 44;

Figure 5 is a fragmentary detail sectional view on an enlarged scale on the plane of the line 55 in Figure 1;

Figure 6 is an exploded perspective view of the front end portion of the body section of the cleaner housing and the filter illustrating these parts in their proper order of assembly, and

Figure 7 is a perspective view of the vacuum cleaner and its suction nozzle with these parts separated to better illustrate the same.

Referring now particularly to the accompanying drawings in which like numerals indicate like parts, the numeral 5 designates generally the tubular housing of the vacuum cleaner, and which comprises a body section 6 and a rear end section 7 removably secured together. At the front end of the housing is a suction nozzle 8 readily detachably secured to the body section by releasable latches 9. A suction fan 10 and its. drive motor 11 are mounted within the housing, and as best seen in Figure 2, the fan is of the centrifugal type and discharges through ports 12 in the rear section of the housing. Attention is directed to the fact that the ports 12 encircle the fan in radial alignment therewith so that the air leaving the fan is discharged in the most direct path possible.

The air entering the fan is, of course, drawn into the suction nozzle where it flows through a channel 13 defined by a partition wall 14 which divides the nozzle interior into the air channel 13 and a dirt collecting pocket 15. From the channel 13 the incoming current of air passes through a filter 16 where its entrained dirt and hair clippings are caught, and then enters the body 6 of the housing to flow longitudinally therethrough and over the drive motor 11 before reaching the fan inlet.

it will be seen therefore, that the air flow through the cleaner may be characterized as straight through since it involves only one relatively abrupt change in direction which occurs in the fan itself and involves no back tracking or reversal of flow which would increase back pressure'and entail larger over-all dimensions. Instead, the most eiiective and powerful suction for a given fan capacity is thus achieved.

The filter 16 is a readily replaceable paper membrane shaped into a shallow bag or basket by a grid 17 and seated in the open front end of the body 6. The grid 17 as best seen in Figure 6 comprises a rim 18 of a size and shape to fit snugly into the front end of the housing 6, andfrom which fingers 19 project rearwardly to protrude into the housing 6 and give the filter membrane its desired bag or basket shape. In this manner the filter area is considerably increased without necessitating enlarging the cross section of the housing. The grid 17 is preferably a plastic molding and has a flange 20 encircling its 7 A l a 3 rim to provide a shoulder which seats upon the front edge of the housing with the edge portion of the filter membrane therebetween.

The mounting of the fan and its drive motor within the housing is achieved with a minimum number of parts and in a most effective and simple manner. It comprises a centrally apertured disc 21 to'one side of which the stator frame 22 of the motor is secured by screws 23 passed through legs 24 on the stator frame and threaded into the disc 21. This secures the motor to the disc with the motor shaft protruding through the aperture in the disc to the other side thereof where the fanis fixed to the shaft. The aperture in the disc thus defines the inlet of the fan, and unrestricted access thereto from inside the housing body 6 is afforded by the large spaces between the legs 24.

An elastic collar 26 of rubber or other similar material tightly embraces a peripheral flange 27 on the disc, and

this elastic collar is clamped between the rear end 28 between the discharge ports 12 in the rear housing sec-" tion 7. Metal washers 31 are preferably interposed between the opposite faces of the elastic collar and the housing parts or shoulders between which it is clamped; and to secure these parts together the rear housing section 7 telescopes over the adjacent rear end of the body 6 and is secured thereto by fastening screws 32.

The mounting of the fan and its drive motor in the manner described thus not only is simple and effective, but because it locates the portion of largest diameter, namely, the fan 10, rearwardly of the housing body portion 6, it achieves a very desirable balance and additionally insulates the housing from the motor both electrically and vibration-wise. a

The described arrangement also permits the body 6 for substantially its entire length to be of smaller cross section than the rear housing section 7, and this has the advantage of enabling the body 6, which serves as the handle for the device, to have a cross sectional size and shape least fatiguing to be held in one hand. Such a shape by experience has been found to be the substantially triangular formation shown particularly in Figure 4, and which is characterized by diametrically opposite respectively, large and small curved portions 33 and 34 connected or joined by relatively flat upwardly divergent side portions 35. Both curved portions 33 and 34 are concentric to the axis of the motor and the fan but the larger curved portion 33,. which may be considered the top of the handle, has a larger radius than the curved portion 34. As a result, a relatively large space 36 is provided across the top of the motor so that the flow of air through the motor housing is greatest across the top of the motor where it is more efiective to dissipate the heat developed by the motor.

The exteriors of the relatively fiat sides 35 and also of the smaller curved portion 34 are longitudinally fluted to define downwardly facing mildly sharp edged ridges 37 to give the handle an easily gripped non-slip surface.

Since the described mounting for the fan and motor does not of itself define the correct angular orientation of the motor with respect to the housing, and especially the position of the leads by which the motor is connected to the terminals of an on-oif switch 38, located on the left side of the housing where it will be easily manipulated by the thumb of the right hand, some means must be provided to assure installation of the motor in a predetermined angular position in the housing. This function is performed by a perforated guard plate 39 secured to the front end of the motor stator in a position normal to the motor axis, and equipped with resilient bumpers 40 which occupy the internal corners defined by the junction of the large radius curved portion 33 with the relatively fiat sides 35 of the housing wall.- The bumpers 40 are conveniently formed by slipping rubber caps onto 4 projections extending from the edge of the guard plate. The guard plate has the additional function of protecting an operator from contact with live parts of the motor during changing of the filter.

- have its free end terminate adjacent to a shoulder 42 encircling the housing slightly rearwardly of the extreme front edge thereof. The free end of the spring blade has its side portions cut away to provide rearwardly facing edges over which hooks 43 projecting rearwardly from the adjacent rear edge of the nozzle engage.

Disengagement of the latches to permit detachment of the nozzle is accomplished by depression of the spring blades through the medium of buttons 44. In one case. the button 44 projects through an opening in the nameplate 44' of the device and in the other case it projects through an opening in a narrow cover plate 46 secured to the housing.

On the inside of the suction nozzle just forwardly of its rearmost edge are four abutments 45 the rear ends of which lie in a common plane so disposed with respect to the extreme rear edge of the nozzle that when the nozzle is in position on the housing these rear ends of the abutments bear against the rim 18 of the filter-shaping grid to hold the same in place.

Attention is directed to the shape of the suction nozzle. As perhaps best seen in Figure 7, the side Walls of the nozzle form substantially coplanar extensions of the relatively fiat sides 35 of the main housing wall, while the top and bottom Walls of the nozzle are curved and converge forwardly toward the axis of the motor so that the mouth of the nozzle is a narrow elongated opening substantially symmetrically disposed with respect to the motor axis. The shape of the nozzle thus not only contributes a great deal to the attractiveness of the unit, but more importantly assures a desirable balance and ease of handling during use.

As noted hereinbefore, the suction nozzle has a partition wall 14 dividing it into an air passage 13 and a dirt collecting pocket 15. This partition Wall is imperforate as is also its junction with the adjacent walls of the nozzle. Accordingly, the nozzle may be immersed in a bath of antiseptic solution to cleanse and sterilize the mouth thereof without entailing wetting of the interior of the dirt collecting pocket, but ofcourse, it should be understood that in doing so the nozzle must not be immersed into the solution to a depth at which the rear edge of'the partition wall 14 lies below the surface of the bath, and that during the immersion the nozzle would be disposed substantially vertically.

Although the purpose of the dirt collecting pocket may be apparent, it might be noted that its location assures that hair clippings and dirt drawn through the air passage 13 and against the filter membrane will drop by gravity and be retained in the pocket, not to .fall back through the mouth of the nozzle if the motor is stopped while the device is held with its nozzle pointing downward.

When not in use, the vacuum cleaner rnay be hung from any suitable support by means of a bail 47. formed integrally with the rear section 7 of the housing. A I

From the foregoing description taken in connection with the accompanying drawings, it will be apparent to those skilled in this art that this invention provides a Vacuum cleaner especially well adapted for use by barbers to remove hair clippings from the head, neck and garments of their customers, and that the invention provides a vacuum cleaner of maximum effectiveness for a given fan size, and one which is well balanced and easily held in one hand.

What is claimed as my invention is:

i.- .In a Yacuunrcleanerv of the character described: a

fan; a drive motor for the fan; a housing for the fan and drive motor formed of complementary front and rear sections joined in end to end relationship; a shoulder on each housing section adjacent to the joint between the sections, said shoulders being spaced apart and facing one another; a centrally apertured motor supporting disc extending across the housing adjacent to the joint between the housing sections; a resilient mounting for said disc clamped between said shoulders and supportingly engaging the peripheral portion of the disc; means securing one end of the stator of the motor to one side of the disc with the motor disposed in the front housing section but with the motor shaft projecting rearwardly through the aperture in the disc and into the rear housing section, the fan being disposed in the rear housing section and being fixed to the motor shaft at the other side of the disc; a suction nozzle on the forward end of the front housing section, ahead of the motor; a perforated guard plate extending across the front housing section between the motor and the suction nozzle, said plate being secured to the forward end of the motor stator; the portion of the front housing section surrounding said guard plate being non-circular in cross section to define a plurality of internal corner portions; and yieldable bumpers on the edge of the guard plate engaging in said corner portions of the front housing section to define the angular position of said apertured disc and the motor thereon relative to the housing, without transmitting motor vibration to the housing.

2. A hand held vacuum cleaner having a suction nozzle at its front, a filter member, a fan, and a drive motor for the fan, the filter member and the fan and its drive motor being mounted in an elongated hollow housing which also provides a handle for the cleaner, characterized by the fact that: the filter member is at the front end of the hollow housing behind the suction nozzle, the fan is at the rear end of the hollow housing with the drive motor located in the medial portion of the housing between the filter member and the fan, said fan being substantially larger in diameter than the motor; the rear end portion of the housing in which the fan is located has air discharge ports therein and has a wall closely encircling the fan; the medial housing portion in which the motor is located provides the handle for the cleaner and has a reduced noncircular cross section with a large radius curved upper portion and a small radius curved lower portion, said curved portions being substantially concentric to the axis of the motor and the rear portion of the housing which encircles the fan and being connected by downwardly convergent opposite side wall portions which are tangent to the small radius curved wall portion and blend with the large radius curved wall portion so that said medial portion of the housing has a generally triangular sectional shape to facilitate gripping and holding the same in one hand; and the nozzle has side walls that form substantially coplanar extensions of said side walls of the medial housing portion and top and bottomwalls that are curved and converge forwardly toward the axis of the motor so that the mouth of the nozzle is a narrow elongated opening the edges of which are substantially symmetrically disposed with respect to the motor axis.

3. A hand held vacuum cleaner having a suction nozzle at its front, a filter member, a fan and a drive motor for the fan, the filter member and the fan and its drive motor being mounted in an elongated hollow housing which also provides a handle for the cleaner, characterized by the fact that: the filter member is at the front end of the hollow housing behind the suction nozzle, the fan is of the centrifugal type and is located in the rear portion of the hollow housing with the drive motor located in the medial portion of the housing between the filter member and the fan; the wall of the rear portion of the housing in which the fan is located has air discharge ports in radial alignment with the fan so that air drawn into the suction nozzle passes through the filter member before flowing longitudinally through the housing, across the motor, and radially out of the ported rear portion of the housing; the rear portion of the hollow housing in which the fan is located is a part separate from the rest of the hollow housing, and removably secured thereto; the rear portion of the housing and the I adjacent medial portion of the housing have facing shoulders thereon; and the mounting of the fan and its drive motor comprises a flat, centrally apertured disc between the fan and the motor, means securing the rear end of the stator of the motor to said disc so as to dispose the motor wholly forwardly of the disc but with the shaft of the motor protruding rearwardly through the aperture in the disc and having the fan fixed thereto at the rear side of the disc, and an elastic collar embracing the periphery of the disc and clamped between said shoulders on the adjacent rear and medial portions of the housing.

References Cited in the file of this patent UNITED STATES PATENTS 1,120,130 Casella Dec. 8, 1914 1,221,221 Rothfeld Apr. 3, 1917 1,577,070 Orr Mar. 16, 1926 1,677,921 Johnson July 24, 1928 1,691,988 Olson Nov. 20, 1928 1,954,416 Leathers Apr. 10, 1934 2,030,367 Grave Feb. 11, 1936 2,372,007 Kroenlein Mar. 20, 1945 2,454,569 Rector Nov. 23, 1948 2,484,491 Daugherty Oct. 11, 1949 2,564,339 Nerheim Aug. 14, 1951 2,626,418 Kelly Jan. 27, 1953 2,635,277 Belknap Apr. 21, 1953 2,652,902 Sheahan Sept. 22, 1953 2,665,445 Foerstel et al. Jan. 12, 1954 2,668,315 Crosby Feb. 9, 1954 FOREIGN PATENTS 147,796 Sweden Nov. 23, 1954 318,200 Great Britain Feb. 27, 1930 500,994 Germany June 27, 1930 600,019 Germany July 13, 1934 654,926 Germany Jan. 4, 1938 

